Before running awesome, a configuration file needs to be created.
Copy the provided ${PREFIX}/share/examples/awesome/rc.lua to
~/.config/awesome/rc.lua and modify as necessary.

To migrate a custom rc.lua from version 3.5.x to version 4.x, see
https://awesomewm.org/apidoc/documentation/17-porting-tips.md.html#v4
